Photovoltaic textiles

ABSTRACT

A tape structure and related circuit configurations for textile systems to establish electrical characteristics of textiles. The textiles incorporate charge carrying components, such as photovoltaic components, in contact with conductive layers in a single tape structure to improve electrical properties without compromising physical characteristics of the textiles. The textiles include photovoltaic tapes, each having an optically transparent layer, a photovoltaic layer, a first electrically conducting layer, a second electrically conducting layer and an insulating substrate located between the first electrically conducting layer and the second electrically conducting layer.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made using funds obtained from the US Government (USArmy, Contract Nos. W911QY-10-C-0015 and W911QY-14-C-0075), and the USGovernment therefore has certain rights in this invention.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to textiles designed for converting electricalcharges, such as charges generated through solar energy, into usableelectricity. More specifically the invention is directed to electricalcharge transfer textiles, photovoltaic systems, solar textiles, andsub-components which reduce electrical resistance for improvedperformance.

2. Description of Related Art

Photovoltaic systems convert sunlight into electricity through theaction of photovoltaic cells. Large solar arrays currently in usetypically have numerous panels or modules, each with many photovoltaiccells. Such arrays have been made from rigid components. More recently,flexible photovoltaic components have been developed that may beincorporated into textiles as alternatives to rigid cells and modules.

Flexible solar energy technology such as polymer photovoltaics (PPV's)holds great promise for many applications. The freedom of movementprovided by textiles has the potential for making solar energyconversion structures that are more easily transported and erected thancomparable rigid solar structures. Such systems could be used to bringmuch needed electricity to remote or disaster ridden areas that wouldotherwise be without power. In other applications, efficient solartextiles integrated into common articles such as hats, garments, tents,and coverings could potentially provide electric power on a smallerscale.

Small cross-section photovoltaic fibers used for solar textileapplications provide uniformity and fabric-like flexibility. Inexpensiveand flexible polymer photovoltaics (PPVs) are well suited for use asfibers. However, attempts at producing efficient solar textiles fromexisting PPV components have been constrained by fundamental technicalbarriers relating to their inherent electrical resistance.

Present PPV fibers of coaxial construction rely on a centered innerconductor and a transparent external conductor, such as ITO (Indium TinOxide) or a conducting polymer such as PEDOT(Poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate)), to move chargealong the fiber. However, when such fibers are incorporated into atextile, the low electrical conductivity of the external, opticallytransparent electrode causes significant voltage drop in the availableelectricity. The voltage drop results because the transparent electrodeprovides two critical but contradictory functions. The first function isto pass solar flux unimpeded through the transparent electrode into theoptically active photoelectric layers beneath the surface. The secondfunction is to move or transport electric charge axially along the sheetdimension of the transparent electrode with minimum voltage drop orloss. Efficient optical transmission requires maximum optical clarity,implying a relatively thin electrode. However, efficient chargetransport requires sufficient thickness to provide a low electricalresistance path. While one function optimizes with increasing thicknessthe other optimizes with decreasing thickness. Currently availableoptically transparent compounds, such as ITO and many of the newpolymer-based substances such as PEDOT, do not simultaneously satisfythe optical clarity and electrical conductivity requirements. For PPVcomponents made from these substances, acceptable optical transmissionresults in excessive electrical sheet resistance for use in solartextiles.

Other photovoltaic fiber designs rely on dual internal conductorsthroughout their length. However, the movement of power through textilesmade from such fibers is generally more complicated and less reliablebecause of the need to make and maintain additional electricalconnections with external circuitry. Furthermore, the small crosssectional dimension typical of internal conductors restricts chargeflow. Similar to co-axial fibers, charge transport along the axis ofdual internal conductor fibers yields large voltage drop, therebydiminishing the performance of textiles in which such fibers are used.

Attempts at producing photovoltaic (PV) fibers for textiles havereported power conversion efficiencies of only 0.01% with electricalfill factors of 24%. (A Photovoltaic Fiber Design for Smart Textiles,Textile Research Journal Vol. 80 (11); 1065-1074 DOI. It has also beenreported that: “An n-type carrier counter electrode that is both highlyconductive and optically transparent has not been reported. Evenindium-tin oxide coatings with a resistivity as low as 10 ohm/cm2 cannottransport the photocurrent generated with 1 sun irradiance over morethan 10 to 15 mm without incurring electrical losses.” (Solar PowerWires Based on Organic Photovoltaic Materials, Science Magazine, 10 Apr.2009.)

In addition to poor efficiency, solar textile modules made fromphotovoltaic fibers known in the art are subject to malfunction fromshorting of conductors, particularly at connections where charges frommultiple fibers are merged. Unless substantially fortified, the delicatenature of the small connections allows them to be damaged from minorimpacts or abrasions. Depending on the design, a single short circuitcould impair the function of multiple cells, or even adjacent solarmodules. Similarly, solar textile modules made from other existingphotovoltaic components such as thin films are either too fragile orrigid and are still largely unproven for exploiting the advantages ofsolar textiles.

A prior design developed and disclosed in PCT application serial numberPCT/US2012/054866 provides a combination of components arranged to forma textile capable of generating electricity from solar energy. Thatprior design used a combination of highly conductive bus bars serving asconduits in contact with photovoltaic tapes or fibers to move charge inand out of textile unit cells. The bus bar conduits are arranged tominimize charge transport resistance throughout the textile by providingmultiple, durable electrical contacts with charged surfaces along thelength of the photovoltaic components. Unfortunately, the configurationsof combinations of PV tapes and bus bar conduits woven together in aninterlacing manner is inefficient in light of the present invention.Specifically, the PV tapes am overshadowed as a result of theover-and-under routing of the bus bar conduits as they pass over the topelectrodes of the PV tapes. This limitation can result in shadowing ofabout 50% of the functional PV tape area. Textiles utilizing the priordesign disclosed in the cited PCT application are also difficult tomanufacture because they rely on multiple components, which increasesthe cost and complexity of fabrication and reduces the likelihood ofwidespread commercialization.

These and other technical problems relating to existing photovoltaiccomponents and systems continue to inhibit the rapid commercializationof new applications for solar textiles. Therefore, there is a need inthe art for more efficient photovoltaic textile components and materialsin general particularly those that are durable but still flexible enoughto exhibit the properties of fabrics.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to novel photovoltaicsystems, components, and methods of manufacturing related to solartextiles. In general, the invention improves solar textile performanceby taking a systems approach to the overall design. Textiles inaccordance with the present invention employ integrated tape structurescontaining both the charge converting PV layer and conductive chargetransport layers. The prior art system disclosed in regard to the PCTapplication referenced above comprises two distinct components, the PVtapes and the conductive bus bar conduits. The two were interwoven andso incapable of utilizing the entire surface area of the solar textileto collect solar energy. The present invention improves manufacturingoptions and substantially eliminates the shadowing limitation byintegrating solar energy conversion and charge transport into a singletape structure. Specifically, the single tape structure comprises firstand second electrically conductive layers sandwiched around aninsulating substrate. The insulating substrate may be a unitary layer orit may be formed of a plurality of layers. A PV layer is applied on atop surface of the first electrically conducting layer. The PV layer maybe a unitary layer or it may be formed of a plurality of layers. The PVlayer provides the photovoltaic functionality while the secondconductive layer performs as a low-resistance transport channel topermit low-loss charge movement along the axis of the tape. One or moreconductive contacts may be positioned on an upper surface of the PVlayer spaced from the first electrically conducting layer by the PVlayer. This design overcomes the limitations previously described bypermitting collection of solar energy across the entire surface area ofthe textile. In addition, by simultaneously providing the neededlow-resistance path to move charge in and out of the textile weave, thesingle tape structure enables the formation of sufficiently efficientcharge carrying textiles suitable for powering devices.

The single tape structure of the present invention can be used as boththe warp and weft components and enables the formation of a solartextile without requiring a separate bus bar conduit. The tape structureof the present invention enables the fabrication of a textile from aweave of a plurality of such tape structures so that various circuitcombinations are available and the output of those circuits is betterthan what is available when separate solar energy converting and chargetransport components are used.

While the description of the present invention is directed to a tapestructure that is suitable for use in a textile system that convertssolar energy to electricity and the effective transport of thatelectricity, it is not limited strictly to “solar” textiles. Instead, itis directed to the inclusion of the tape structure in any textile thathas one or more flexible and elongated charge carrying components, whichmay be photovoltaic components but that also may be other forms ofcharge carrying components, including, but not limited to, other formsof flexible conductive elements.

The foregoing and related aspects and embodiments and other advantagesand features of the invention will be readily apparent to those skilledin the art after review of the following detailed description of theinvention, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross section of an integrated tape structure including a PVportion and two electrically conducting layers spaced from one anotherby an insulation layer. FIG. 1A is a cross section of the PV conversionlayer of the integrated tape structure.

FIG. 2 is a cross section of the integrated tape structure of thepresent invention with the insulation layer comprised of a plurality ofsublayers.

FIG. 3A is a top perspective view of a portion of a solar textile of thepresent invention formed with the integrated tape structure of FIG. 1and FIG. 3B is a bottom perspective view of the portion of the solartextile of FIG. 3A.

FIG. 4 is a perspective view of the solar textile of the presentinvention formed with the integrated tape structure of FIG. 1 withterminations at both tape ends.

FIG. 5 is a cross section of an alternative embodiment of the tapestructure showing a curved version of the second electrically conductinglayer.

FIG. 6 is another alternative embodiment of the tape structure showingthe second electrically conducting layer spaced from the insulationlayer.

FIG. 7 is cross section side view of the embodiment of the tapestructure of FIG. 6.

FIG. 8 is a bottom perspective view of a textile including the tapestructure configuration of FIG. 6.

FIG. 9 is a top perspective view of an embodiment of a textile includingthe tape structure of the present invention including a way to increasecontact between adjacent tapes.

FIG. 10 is a top perspective view of the textile of FIG. 9 showinginternal expansion within the tape structure to enhance contact betweenadjacent tapes.

DETAILED DESCRIPTION OF THE INVENTION

The term “deposit” covers all technologies used in coating a surfacewith a material including but not limited to spraying, dipping, spincoating, vacuum and chemical deposition, printing including, but notlimited to, inkjet printing.

The term “light” includes a range of electromagnetic radiation known asvisible light and portions of infrared and ultraviolet spectrumsapplicable to generating electricity from photovoltaic components.

The term “photovoltaic” means having a capacity to contribute to theproduction of electricity across opposite electrodes as a result ofbeing exposed to electromagnetic radiation.

The abbreviation “PPV” is short for polymer photovoltaic and describes acomponent or system having photovoltaic function which includes astructural polymer and other materials.

The abbreviation “PV” is short for photovoltaic and describes acomponent or system having photovoltaic function, wherein thephotovoltaic may not be a polymeric component.

The term “PV layer” refers to one or more photoactive layers that whencombined with another will facilitate the generation and movement ofelectric charge.

The term “solar textile” includes textiles, cloths, fabrics, and otherwoven assemblies incorporating photovoltaic components and havingvarying degrees of flexibility.

The term “tape” refers to a relatively thin and narrow component withtwo opposing planar surfaces that is particularly longer than it iswide.

The term “transparent” means allowing light to pass through and includestranslucent as well as transparent.

Photovoltaic systems according to the present invention comprisetextiles made by weaving together integrated textile tape structures ofthe form described herein.

In preferred embodiments, systems of the present invention incorporateconductive tape structures of the configuration described herein. Shownin FIG. 1 is a cross section of an integrated single tape structure 10of the present invention. The tape structure 10 includes a PV conversionlayer 12 that may be a polymeric photovoltaic tape but is not limited tothe inclusion of polymeric material in its fabrication. The PVconversion layer 12 contacts a first electrically conducting layer 14that may be a structural support of the PV conversion layer 12. Thefirst electrically conducting layer 14 is flexible and conductive anddefines the active width of the PV conversion layer 12. The firstelectrically conductive layer 14 can be a metal, such as aluminum, aconductive polymer or a stack of layers of metal and conductive polymerschosen to achieve simultaneously, good electrical conductivity,mechanical strength and flexibility. As shown in FIG. 1A, the PVconversion layer 12 is fabricated of an electron absorbing sublayer 22in contact with the first electrically conducting layer 14, a photonabsorbing photoactive sublayer 24, and an optically transparent holetransport sublayer 24. The optically transparent hole transport sublayer26 serves as an upper electrode 26 of the tape structure 10. The firstelectrically conductive layer 14 and the PV conversion layer 12 aresequentially in physical and electrical contact with one another,forming the junction structure needed for photovoltaic conversion. Ingeneral other structures may provide the photovoltaic conversionprovided by the PV conversion layer 12 without deviating from theinvention.

The optically transparent upper electrode 26 may be formed of ITO orPEDOT or any suitable optically transparent material having someconductivity. That is, the upper electrode 26 is fabricated of amaterial that is selected to allow light 28 representing solar energy topass therethrough. The light 28 passes through the upper electrode 26and reaches the photon absorbing photoactive layer 24, which enablesmovement of electrons to the electron absorbing layer 22. Thephotoactive layer 24 may be fabricated of P3HT:PCBM(poly-3-hexylthiophene and [6,6]-phenyl C61 butyric acid methylesterblend). The electron absorbing layer 22 may be fabricated of Zinc Oxide.Those of skill in the art will recognize that other options for formingthe indicated sublayers of the PV conversion layer 12 are possible. ThePV conversion layer 12 may simultaneous overlay both the firstelectrically conducting layer 14 and a portion of the insulatingsubstrate 32 in such a manner as to establish an insulating marginaround the edges of the first electrically conducting layer 14 to ensureelectrical separation between otherwise highly conductive layers of thetape structure 10 itself or highly conductive layers of adjacent tapestructure layers used to form a solar textile. That optionalconfiguration of the PV conversion layer 12 and the first electricallyconducting layer 14 is shown in FIG. 5.

The photoactive and accompanying layers of materials that form the PVconversion layer 12 may be deposited on the first electricallyconductive layer 14 and assembled together using present depositionmethods known in the art. One or more contacts 30 may be affixed to anupper surface of the upper electrode 20 and may be used to establish anelectrical connection to the upper electrode 26. Contacts 30 are madefrom a highly conductive material, such as the same material as thefirst electrically conducting layer 14.

The remainder of the tape structure 10 includes an insulation layer 32and a second electrically conducting layer 34. The insulation layer 32is fabricated of one or more materials selected to electrically insulatethe second electrically conducting layer 34 from the first electricallyconducting layer 14 of the tape structure 10. The insulation layer 32may be fabricated as a unitary structure or it may be fabricated of twoor more sublayers. For example, as shown in FIG. 2, the insulation layer32 may be formed of a first insulation sublayer 36 and a secondinsulation sublayer 38. The first insulation sublayer 36 and the secondinsulation sublayer 38 may be formed of the same or different materials.They may be physically connected together so that they move in unisonwhen the tape structure 10 moves or they may be allowed to movedifferently with respect to one another to enhance the flexibility ofthe tape structure 10 as part of a textile. The insulation layer 32 maybe fabricated of a nonmetallic material such as polyester, polyimide,polyethylene terephthalate, for example, or other material havingstructural characteristics suitable for maintaining the structuralintegrity of the tape structure 10 when used for its intended purposeand that is also sufficiently electrically insulative so that no shortoccurs between the first electrically conducting layer 14 and the secondelectrically conducting layer 34.

The second electrically conducting layer 34 is formed of a material andwith dimensions similar to that provided for the first electricallyconducting layer 14. That is, it is flexible and conductive and mayextend to the perimeter or be recessed at its perimeter with respect toits width versus the width of the insulation layer 32. It can be ametal, such as aluminum, for example, a conductive polymer or a stack oflayers of metal and conductive polymers chosen to achieve simultaneouslygood electrical conductivity, mechanical strength and flexibility. Thesecond electrically conducting layer 34 of one of the tape structures 10is arranged to make electrical contact with the PV conversion layer 12of an adjacent different one of the tape structures 10 when a pluralityof the tape structures are combined such as by weaving into a textile.That is, the second electrically conducting layer 34 of one of the tapestructures 10 has a potential substantially corresponding to that of theupper electrodes 26 of the PV conversion layer 12 of another one of thetape structures with which it makes contact. The first electricallyconducting layer 14 in that instance has a lower potential than that ofthe second electrically conducting layer 34.

When finished, the tape structure 10 can be rolled for storage orshipment, for example, and then be unrolled and fed as needed info loomsof various types to create numerous textile weaves.

FIGS. 3A and 3B show an embodiment of a textile 100 of the presentinvention using a plurality of the tape structures 10 of FIG. 1 or FIG.2 as an assembled weave whereby each of the plurality of tape structures10 has the PV conversion layer 12 with one or more optional contacts 30on an upper side 40 thereof and the second electrically conducting layer34 on a bottom side 42 thereof. The first electrically conducting layer14 lies between the PV conversion layer 12 and the insulation layer 32,while the second electrically conducting layer 34 is on the oppositeside of the insulation layer 32, forming the bottom side 42 of the tapestructure 10. The second electrically conducting layer 34 makes contacteither with the contacts 30 or directly to the PV conversion layer 12.The contacts 30 are highly conductive and no significant voltage drop isexpected along the length of the tape structure 10 when two tapestructures 10 are put together.

Electrical termination with external circuitry may be accomplished byexposing ends 44 of the first electrically conducting layers 14. A bulkclamping system can also be used to establish the electrical connectionto external circuitry. For example, since the tape structure 10 is of auniform bipolar, bidirectional nature, a simple bipolar, mechanicalcompression clamp may be used to make electrical connections to completean electrical circuit. When the connections are made, electrical currenttravels in a circuit from the terminal established at the interfacebetween the PV conversion layer 12, or the contacts 30 if present, andthe second electrically conducting layer 34 of separate cross-woven tapestructures 10 and returns through the relatively lower potentialterminal established at the ends 44 of the first electrically conductinglayer 14.

The textile incorporating the tape structure 10 of FIGS. 1 and 2 can bescaled to larger sizes as shown in FIG. 4. Note that the electricalterminations are bulk macroscopic terminations without the need toseparate individual polarities since the tops of the tape structures 10are always one polarity and the intermediate sections of the tapestructures 10 at the ends 44 of the first electrically conducting layer14 are effectively the other polarity. Additionally, FIG. 4 shows thatterminations can be made at both ends 44 of the tape structures 10,which should minimize voltage drop. It is also evident from thesefigures that this tape structure configuration eliminates the shadowinglimitation evident with the prior design since all exposed surfaces ofthe textile are photoactive. This configuration is also easier tomanufacture than prior designs requiring the use of two separatestructures, one for converting solar energy and the other fortransporting the convened electrical signals.

An alternative embodiment of the tape structure 10 is represented inFIG. 5. In this embodiment, the second electrically conducting layer 34is curved or arched to enable its conformance with an underlyingadjacent tape structure 10 that is curved as a result of its flexibilityand any movement of the manufactured textile including the tapestructure 10. This serves multiple purposes: 1) the curved surfaceapproximately matches the curvature of the under arching tape, therebyincreasing the effective contact area between the tapes, and 2) contactpressure is more uniformly distributed over the area of contact. Theresult is a more uniform and controlled electrical interface between theover and under arching tapes.

FIG. 6 illustrates a design alternative that maintains the desirableelectrical properties of the two metal electrodes while minimizing theimpact on tape stiffness. This is accomplished by separating the secondelectrically conducting layer 34 from the insulation layer 32, albeitwith some physical connection maintained, thereby enabling mechanicalshear to occur between the layers. This eliminates I-beam behavior andreduces layer stress arising from tape flexure. FIG. 7 shows the sameseparated design shown in FIG. 6 but with a curved cross section of thesecond electrically conducting layer 34. Other cross section designs arealso possible. FIG. 8 shows the bottom curved electrode that is thesecond electrically conducting layer 34 as it would be implemented in aweave.

An aspect of achieving desired good tape-to-tape electrical contact in atextile comprising a plurality of the tape structures 10 combinedtogether is to force the tapes to establish more surface area contactwith one another. An applied force packs the adjoining tapes closertogether, and through tape flexure, increases contact pressure betweenthe over and under arching tapes arising from the lighter radius ofcurvature of the tapes that can be established. It is also possible toincrease tape-to-tape contact pressure by expanding the tape crosssection. FIG. 9 shows a simple rectangular cross section tape arrangedto include an expansion element 50 in an unexpended configuration. FIG.10 shows the same tape of FIG. 9 but with the expansion element 50 in anexpanded configuration. The expanded form of the expansion element 50causes the tape to take on a convex shape so that adjacent tapes thatare so expanded will have greater contact between their respectivesecond electrically conducting layers 34 and PV conversion layers 12.One example of a way to provide the expansion element 50 is to form apouch within or adjacent to the insulation layer 32 and insert a fluidto expand the pouch. Another way is to form a portion, as shown in FIGS.9 and 10, of the insulation layer 32 of an expandable material, such asan expandable temperature-active foam and apply fluid pressure to thefoam. The insulation layer 32 may also be fabricated of such a materialand thereby become the expansion element 50.

Embodiments of the tape structure 10 for textiles described thus far areonly examples of the many that may be constructed according to thepresent invention. Textiles having other weaves attaining functionalobjectives of the present invention are possible using the same PVconversion layer 12, first electrically conducting layer 14, insulationlayer 32 and second electrically conducting layer 34. Moreover, amultitude of textile products are made possible by varying the geometricstructures of the tape structures 10 as well as their orientations withrespect to one another.

As described herein, persons skilled in the art will understand thatnovel systems, components, and methods for fabricating improved solartextiles are herein disclosed which resolve significant shortcomings inthe prior art. The embodiments provided are intended only as exemplaryillustrations and not for the purpose of limiting the scope of claimswhich might be sought to the present invention. Various changes,modification, and equivalents in addition to those shown or describedwill become apparent to those skilled in the art and are similarlyintended to fall within the spirit and scope of the invention whether ornot they presently exist in the following or are later made in amendedclaims.

What is claimed is:
 1. A photovoltaic tape structure for use in atextile having multiple layers, the photovoltaic tape structurecomprising: a) an optically transparent upper electrode; b) aphotovoltaic layer for converting light energy into electricity, whereinthe photovoltaic layer is located below the optically transparent upperelectrode; c) a first electrically conducting layer located below thephotovoltaic layer; d) an insulation layer located below the firstelectrically conducting layer; and e) a second electrically conductinglayer located below the insulation layer.
 2. The photovoltaic tape ofclaim 1 wherein the tape has one or more electrically conductiveelectrodes along the upper surface of the tape to provide contact pointsfor the transport of charge.
 3. The photovoltaic tape of claim 1 whereinthe second electrically conducting layer is of a curved configuration.4. The photovoltaic tape of claim 1 wherein the insulation layer isformed of a first insulation sublayer and a second insulation sublayer,wherein the first insulation sublayer is joined to the firstelectrically conducting layer and the second insulation sublayer isjoined to the second electrically conducting layer.
 5. The photovoltaictape of claim 1 wherein the second electrically conducting layer isslidingly spaced from the insulation layer.
 6. A photovoltaic textilecomprising a plurality of photovoltaic tape structures woven together inan interlacing manner wherein each of the photovoltaic tape structuresincludes: a) an optically transparent upper electrode; b) a photovoltaiclayer for converting light energy into electricity, wherein thephotovoltaic layer is located below the optically transparent upperelectrode; c) a first electrically conducting layer located below thephotovoltaic layer; d) an insulation layer located below the firstelectrically conducting layer; and e) a second electrically conductinglayer located below the insulation layer.
 7. The photovoltaic textile ofclaim 6 wherein a first set of the plurality of tape structures arearranged substantially parallel to one another and a second set of theplurality of tape structures are arranged substantially parallel to oneanother, wherein the tape structures of the first set are interlacedwith the tape structures of the second set in a substantiallyperpendicular arrangement.
 8. The photovoltaic textile of claim 7wherein the second electrically conducting layer of the first set oftape structures contacts the optically transparent upper electrode layerof the second set of tape structures and the second electricallyconducting layer of the second set of tape structures contacts theoptically transparent upper electrode layer of the first set of tapestructures.
 9. The photovoltaic textile of claim 6 wherein the tape hasone or more electrically conductive electrodes along the upper surfaceof the tape to provide contact points for the transport of charge. 10.The photovoltaic textile of claim 6 wherein the second electricallyconducting layers of the plurality of tape structures are of a curvedconfiguration.
 11. The photovoltaic textile of claim 6 wherein theinsulation layers of each of the plurality of tape structures are eachformed of a first insulation sublayer and a second insulation sublayer,wherein the first insulation sublayers are joined to their respectivefirst electrically conducting layers and the second insulation sublayersare joined to their respective second electrically conducting layers.12. The photovoltaic textile of claim 6 wherein the second electricallyconducting layers of the plurality of tape structures are slidinglyspaced from their respective insulation layers.
 13. The photovoltaictextile of claim 11 wherein each first insulation sublayer is allowed tomove differently with respect to its corresponding second insulationsublayer.
 14. The photovoltaic tape of claim 4 wherein the firstinsulation layer is allowed to move differently with respect to thesecond insulation sublayer.